Material handling apparatus



Sept 10, 1940# H. H. MERwlN ET Al. 2,214,340

MATERIAL HANDLING APPARATUS I Filcd Nov. 5, 1938 5 Sheets-Sheet l FIG. l

H H. usew//v f w. REY/vows RYIvw-LAM ATTORNEY Q By Sept. l0, 1940- H. H. Mx-:RwlN ET AL 2,214,340

MATERIAL HANDLING APPARATUS Filed Nov. 5, 1938 3 Sheets-Sheet 2 FIG. 6

/NVENTORS H./. MERW//V E W. REYNOLDS A TTOR/VEV Sept. l0, 1940. H. H. MERWIN ET AL 2,214,340

MATERIAL HANDLING PPRATUS FilOd HOV. 5, 1938 3 Sheets-Sheet 3 FIG 4 FIG. 3

INVENTORS H. H. ME/PW/N E. W. REYNOLDS ATTORNEY Patented Sept. 10, 1940 UNITED STATES PATENT OFFICE MATERIAL HANDLING APPARATUS Application November 5, 1938, Serial N o. 239,002

23 Claims.

This invention relates to a material handling apparatus, and more particularly to an apparatus for serving a covering material on an advancing core.

In forming coverings on cores, for example in wrapping a tape from a pad spirally about an advancing core, a serving head supporting the pad is, in some instances, rotated about the advancing core and frequently in such instances the decrease in the weight of the pad as the tape is removed therefrom causes an unbalancing of the serving head affecting the smooth and uniform operation ofthe apparatus.

An object of the invention is to provide an eilicient and uniformly operable constantly balanced material handling apparatus.

With this and other objects in view, the invention comprises an apparatus having a rotary unit axially apertured for the advancement of a core to be covered, the serving head including a support for a pad of serving material rotated as the material is removed from the pad to actuate a valve to release predetermined quantities of a fluid from one chamber to another to cause constant balancing of the serving head as the weight of the pad varies.

Other objects and advantages will be apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein:

Fig. 1 is a front elevational View of the apparatus, portions thereof being broken away;

Fig. 2 is an end elevational view, portions thereof being broken away;

Fig. 3 is an enlarged fragmentary sectional view taken along the line 3-3 of Fig. 1;

Fig. 4 is a fragmentary sectional view taken substantially along the line 4--4 of Fig. 3;

Fig. 5 is a fragmentary sectional view taken along the line 5-5 of Fig. 3;

Fig. 6 is a fragmentary sectional view taken along the line 6-6 of Fig. 2; and

Fig. 7 is a schematic 'view of the apparatus to illustrate the balancing of a rotary unit therein.

Referring now to the drawings, wherein like reference numerals designate similar elements throughout the views, numerals I 0 and II designate end frame supports of the general structure and contour shown in Figs. 1 and 2 and connected to each other by brace rods I2. Suitable bearings I3 and I4 are mounted uponv the supports I0 and Il, respectively, to rotatably support a unit I5 which, in the present embodiment, is a serving head capable of serving tape spirally about an advancing core.

The rotary unit I5 is composed of head members I8 and I9 of the general contour illustrated in Figs. 1 and 2 and formed of suitable material, such as sheet metal, having side edges bent outwardly at right angles, as indicated at 20, to form 5 reenforcing flanges. Adjacent the center of the head member I8, an aperture is formed to receive a hollow shaft 22 which is rigidly mounted upon the head member, its central aperture serving as a passageway for a core 23. As shown in Fig. 1, the shaft 22 is journalled in the bearing I3. The head member I9 is similarly apertured at its center, where a hollow shaft 25 is rigidly mounted and journalled in the bearing I4, the central aperture of the shaft serving also as a passageway for the advancing core 23. At the outer end of the shaft 25 suitable means is provided to connect the shaft witha power means (not shown) to rotate the unit, the means suggested in this embodiment being a sprocket wheel-26 and a chain 20 21.

The head members I8 and I9 are connected together to form a rigid frame by means of groups 29 and 3l) of angle members having their ends rigidly secured to the head members by any suitu able means such as Welding. By viewing Figs. 1 and 2, it will be observed that there are four angle members in each group 29 and 30, so positioned as to provide spaced horizontal parallel walls between the four members in each group, when the unit is in the position shown in Fig. 2, and parallel vertical walls between the inner pairs of angle members of each group. Between the spaced horizontal walls in the groups of angle members 29 and 30 are disposed supporting arms 35, 36, 3l and 38. The supporting arms are substantially square in cross sectional contour, yet they are reduced adjacent the centers thereof so as to be received between the horizontal parallel Walls shown in Fig. 2 and thus be rigidly se- 40 cured and supported by the groups of angle members constituting a part of theframe of the rotary unit. The supporting arms are spaced as illustrated in Figs. 1 and 2 and the outer ends thereof are apertured, the outer ends of the arms 35 45 and 36 being apertured to receive locking pins 40 while the outer ends of the arms 31 and 38 are apertured to receive pivot pins 4I.

'Ihe pivot pins 4I support frames 43 and 44, which frames might hereinafter be referred to i, as pivotal frames. The pivotal frames consist of spaced fiat strips 45 having their ends secured to strips 46, bent so that the central portions thereof, as illustrated in Fig. 2, are spaced from their respective strips 45. 'I'he upper ends of the 55 the pivot pins 4|. The lower ends of the strips 45 and 46 are secured to each other and to apertured lugs 48 for receiving the locking pins 40. The locking pins 40 are removable to permit swinging of the pivotal frames about their pivots and are each provided with a handle at one end, their other ends having circumferential grooves to receive spring pressed latches 49 carried by the arm 36 to lock the pins in place. l

Considering one pivotal frame, attention is directed to Figs. 2, 3 and 4, where there is shown a supporting Iplate 50 disposed between the sets of strips 45 and 46 constituting the frame sections, as illustrated in Fig. 4, and having reduced projections 5| extending between the plates of the frame sections, where they rest upon supporting blocks 52. Each strip 45 of the pivotal frame sections has one of the blocks 52 mounted thereupon for supporting the projections 5| of the supporting plate 50.

having enlarged portions overhanging the projections, are disposed and secured in place by any suitable means, such as machine screws, to firmly secure the supporting plate 50 in the pivotal frame 44.

As shown in Fig. 3, a bearing supporting housing 55, having a flanged inner end secured to the supporting plate 50 by suitable means, such as machine screws, is of a suitable contour to receive therein bearings 56 and 51 to rotatably support an arbor shaft 58 upon which an arbor 59 is mounted. The arbor 59 is arranged to removably receive a pad 60 (Fig. 2) of material such as paper tape, which is to be served upon the core 23. A disk-like member 6| threadedly mounted upon the arbor supports the pad 60 at one side thereof. Adjacent the member 6| on the arbor, a ring gear 62 is mounted-and interengages a gear 63 to rotate a shaft 64 upon which the gear 63 is mounted. The shaft 64 is rotatably journalled in a bearing 65 .supported by an integral projection 66 of the supporting plate 50.

A fluid housing 10 composed of cylindrical portions 1| and 12 and a, cover portion 13 are secured together and to the supporting plate 50 by suitable means, such as bolts, extending through the outer portion of the cover portion 13 and an integral annular anged portion 15 of the cylindrical portion 1|.

The cylindrical portion 1| composes slightly less than half the housing`10 and houses an inner chamber 16. The housing 12 is of the genral contour shown in Fig. 3, providing an outer chamber 11 anda dividing portion or partition 18. The partition 18 has a concave wall 19 to `close the inner chamber 16 and an integral hollow central projection extending through the inner chamber and having its end embedded in a recess in the end wall of the cylindrical portion 1 I. Outlet openings or passageways 8| are formed in the central projection 80 at diametrically opposed positions adjacent the concave Wall 19 to iprovide outlets for the inner chamber 16. A

valve is rotatably disposed in the hollow central projection portion 80 and extends through the partition 18, as shown in Fig. 2. Apertures 86 extend transversely through the valve 85 at spaced positions and are connected to each other by an axially disposed aperture. The combined apertures 86 with their connecting axial aperture are substantially H-shaped and one of the apertures 86 is positioned to communicate with the At each side of eachY projection 5| and block 52 retaining lugs 53,

strips 45 and 46 are secured 4to each other andl to bearing members 41 rotatably mounted upon passageways 8|. A passageway-81 in the partition 18 disposed at right angles with respect to the axis of the passageways 8| is positioned to communicate with the other aperture 86. It will, therefore, be observed that the valve 85 when in the position shown in Figs. 3 and 4, will position the apertures 86 and their connecting axial aperture in communication with the pas sageways 8| and the inner chamber 16, whereas rotation of the valve one quarter of a revolution will cut olf communication between the valve apertures and the passageways 8| and move the valve apertures into communication with the passageway 81 which lies within the outer chamber 11.

The valve 85 extends into the chamber 11, where it has secured thereto a bevelled gear 90, and is journalled in a suitable bearing 9| disposed between tlie bevelled gear and an internally extending integral sleeve portion 92 of the cover portion 13. The bevelled gear inter- Yengages a bevelled gear 94 which is mounted upon the inner end of a shaft 95, the shaft being journalled in suitable bearings 96 and sealed by any suitable packing 91. The bearings 96 are supported in a bracket 98 mounted upon the housing 10, which in turn supports a bearing bracket |00 for a bearing |0| in which the shaft 64 is journalled. Bevelled gears |02 and |03 operatively connect the shaft 64 and 95, respectively. y

A uid |05, such as mercury, is disposed in the inner chamber 16, the quantity of the fluid depending upon the weight of the pad 60 of material. A plug |06 in the cover portion 13 may be removed for pouring the fluid |05 in the housing. Due to passageways |01 and |08 in the sleeve 92 the fluid may pass therefrom into the outer chamber 11. In order to allow the fluid to pass from the outer chamber 11 to the inner chamber 16 the unit I5 may be rotated until the housing is in a vertical position, the chamber 16 being beneath the chamber 11, at which time a threaded valve ||0 may be actuated to open communication througha passageway (shown in Fig. 5) between the chambers 16 and 11. After the :duid has passed into the inner chamber 16 the valve I0 may be closed, cutting oi communication between the chambers other than through `the valve 85.

Means is provided to direct tape ||5 from the pad 60 to the advancing core 23, where the tape is wound spirally about the core during rotation of the unit I5. This means consists of a frame 6 of the contour shown in Figs. 1 and 2 and comprising a flat portion I|1 having its outer edge disposed between the vertical parallel walls of the inner members of the groups 29 and 30 of the angle members, as shown in Fig. 2, and having a central hollow hub portion ||8 for receiving a tubular guide H9 for the passage of the core 23 therethrough. The tubular guide ||9 supports the core for some distance upon each side of the hub I8 and is slotted at |20 to receive the tape during the forming of the tape upon the core. A ro1ler.|2| supported by the angle members 29 is positioned to receive the tape from the pad 60. The tape is passing from the roller |2| is drawn transversely across the rotary unit, where it passes between a pair of rollers |22 and |23 over the roller |23 and around a roller |24, Where the tape is directed through one of the slots |20 in the guide H9. The roller |23 is rotatably mounted upon a bracket |25 carried by the portion ||1 of the frame H6, while the roller |22 may be termed a tension roller and is also supported by the bracket |25 and urged into close engagement with the tape by means of a spring |26.

The drawings illustrate the rotary unit I5 with one serving unit and one material directing means for applying a covering on the core 23 of the single tape taken from the pad 60. When only one serving mechanism is employed a weight member I 30 is mounted upon the supporting plate 50 of the other pivotal frame 43, as shown in Fig. 2, the weight o'f the member |30 being equal to the serving mechanism carried by the other pivotal frame including a full pad 60 with the fluid |05 in the inner chamber 16. It is to be understood, however, that the invention includes as one embodiment the rotary unit l5, with a serving mechanism carriedby each pivotal frame and a material directing means for the tape of each mechanism to simultaneously wrap two tapes spirally about the core. It is not believed necessary to add to the drawings figures illustrating the rotary unit with two serving mechanisms and two material directing means, but that such an embodiment of the invention may be fairly understood from the present disclosure.

Considering rst the operation of the apparatus with the single serving mechanism and a single directing means, let it be assumed that a full pad 60 is mounted upon the arbor 59, that the free end of the tape is threaded around the roller 2| between the rollers |22 and |23 around the roller |24 and extended through slot |20 in the guide ||9, where the tape is wound about the core 23 sufficiently to start the wrapping thereof when the apparatus is set in motion. When the tape is suitably threaded and the fluid |05 is in the chamber 16 the apparatus may be set in motion through the connection of the chain 21 to the power means (not shown) to rotate the unit |5 in the direction of the arrow (Fig. 2). During this rotation of the unit the tape ||5 will be withdrawn from the pad, causing rotation of the pad and in turn causing rotation of the arbor 59.

Attention is now directed to Figs. 2 and 3, wherein it will be observed that rotation of the arbor 59 will cause rotation of the gear 62, the gear 63, the shaft 64, the bevelled gear |02, the bevelled gear |03, the shaft 95, the bevelled gear 94, the bevelled gear 90, resulting in rotation of the valve 85. Rotation of the unit I5 causes the fluid |05, through centrifugal force, to pass in limited quantities through the passageways 8| and into the apertures 86 and their connecting axial apertures. The quantity of the fluid leaving the chamber 16 is limited by the capacity of the valve apertures. This quantity of iiuid is allowed to pass, by means of centrifugal force, from the valve apertures and through the passageway 81 into the chamber 11, when the valve 85 is rotated a sucient distance to move the valve apertures into communication therewith. It will, therefore, be understood that as the tape is withdrawn from the pad and the pad becomes lighter in weight the fluid |05 is transferred in limited quantities from the inner chamber 16 to the outer chamber v11 and, due to centrifugal force, the fluid in entering the outer chamber 11 will lie against the inner Wall of the cover portion 13 and gradually build up toward the partition 18 past the outer chamber is gradually filled with the fluid. The fluid controlling means, namely the valve 85 with its associated passageways and apertures, is so linked with the arbor 50 and the pad carried thereby, that the uid weight is moved outwardly to effectively increase the weight at the serving side of the rotary unit to compensate for the decrease in weight of the pad 60 during the removal of the tape therefrom. To illustrate this feature, attention is directed to Fig. 7, which schematically illustrates the serving mechanism and its association with the advancing core. The chambers 16 and 11 are so proportioned that when d1 d2 are the displacements at the start and end of the cycle and r1 r2 are maximum and minimum radii of the pad 60. If w=weight of the fluid |05 then wD=WR. In the present embodiment the fluid |05 is mercury and the weight of the mercury w=weight of the pad W; then D, displacement of mercury during a full cycle=R, eccentricity of the pad. Therefore, the moments of inertia of the two masses, namely, the material and the fluid being equal the centrifugal forces thereof are equal.

In this embodiment, during the shifting of weight in the serving mechanism to compensate for the variation in weight of the pad the weight of the member |30, of course, remains constant. In other words, the serving mechanism automatically controls the weight of one side of the serving head during the removal of the tape or the constant decreasing in weight of the pad to maintain a balance of one side of a rotary unit with a constant standard on the other side thereof. In this manner the rotary unit is balanced at all times regardless of variations in the weight of the pad, making it possible to rotate the unit at a high rate of speed without vibration or other damaging effects resulting from unbalanced units. The smooth and uniform rotation of the balanced rotary unit eliminates wear and makes possible the uniform application of the material uponthe core at a higher rate of speed than would be possible with an unbalanced rotary unit.

When the material of the pad is paid out and the fluid from the inner chamber has passed into the outer chamber the apparatus may be stopped and conditioned for further service. To condition the apparatus for further service the locking pin 40 of the pivotal frame 43 carried by the serving mechanism is removed by moving the spring pressed'latch 49 free of the slot in the pin. 'I'he pivotal frame with the serving mechanism may then be moved arcuately, as illustrated in dotted lines in Fig. 2, to a position where a new pad 60 may be inserted in place upon the arbor 59. During the placing of the new pad upon the arbor the threaded valve ||0 is actuated to open the vpassageway and allow the uid to pass from the outer 'chamber 11 by means of gravity into the inner chamber 16. When this has been accomplished the valve l0 is closed and the serving mechanism on its pivotal frame may be swung in position and locked in place by its pin 40.

When it is desirable to employ two serving mechanisms the weight member |30 is removed from its supporting plate 50 and a serving mechanism, identicall in -construction and operation to the one illustrated and described, is secured in place upon the said supporting plate so as to provide two serving mechanisms, one upon each side of the advancing core. The directing means for the second serving mechanism will be identical to that shown for the rst serving mechanism, the only difference being in the position thereof, the position being to direct this tape to the core at a position diametrically opposed the point of serving oi.' the other tape. For this purpose there are two elongate slots |20 in the tubular guide H9 at diametrically opposed positions. When two serving mechanisms are employed let it be assumed that at the beginning of the operation the pads 60 of both mechanisms are full and that the fluid |05 in each housing is disposed in the inner chamber 16. In this instance rotation of the unit l5 will cause the pads to decrease in weight simultaneously and if the tapes should be withdrawn at the same speeds the weight of the pads would be maintained equal at all times during the serving, and like quantities of fluid would be transferred to each outer chamber 11 from their respective inner chamber 16. However, the rotary unit will be equally balanced at all times during its rotation, regardless of the comparative sizes and weights of the' pads and the relative speeds at which the tapes are removed, due to the fact that the auxiliary weight of each portion of the unit, namely the uid |05 therein, is varied or transferred from the inner cham- Vber to the outer chamber thereof, dependent upon the variation of the Weight in its respective material or pad 60. In other Words, each portion of the unit, that is, each serving mechanism, is independent of the other, yet it is so operated that the effective weight of its half of the unit will at all times be equal to the effective Weight of the other portion or serving mechanism, regardless of the size or Weight of its pad, and may in this manner result in the independent operation of each portion of the unit to maintain an effective balancing of the unit.

In the present embodiment of the invention the material H5 of the pad 60 is paper tape, but it should be understood that any substance may be used, the purpose of the invention being to maintain the rotary unit I5 balanced during variation or decrease in weight of the substance carried thereby. This balance is maintained by the shiftingof an auxiliary weight means, which in the present embodiment is a fluid, for example, mercury, transferred in quantities under the control of the rotary element or arbor 59, which is rotated during the removal of the material. It is apparent that during rotation of the unit l5 at a constant speed the material or tape will be withdrawn from the pad at a constant speed. However, the arbor or element 59 will not be rotated at a constant speed but the speed of rotation thereof will be gradually increased as the diameter of the pad 60 decreases. I'he valve 85 being controlled by the rotation of the arbor gradually.v increases in speed with the increase in speed of the rotation of the arbor. It will be observed that during the slower rotary movement of the valve 85, which occurs when the pad 60 is full, the quantities of fluid released from the inner chamber and passing into the outer chamber will, due to centrifugal force, pass outwardly to the cover portion 13. These quantities of fluid will build up inwardly from the cover portion 13 with gradual increasing rapidity during the decrease in diameter of the pad. Now, therefore, with each quantity of uid being substantially equal in weight to the weight of the material which has been removed from the pad during the transfer of this quantity of uid from the inner chamber to the outer chamber, the unit is maintained balanced. These quantities of iiuid are most effective when in the outermost positions adjacent the cover portion 13 to counterbalance the unit and to compensate for the material removed from the pad, these quantities becoming slightly lessy effective, however, as the body of fluid in the outer chamber 11 builds up toward the axis of rotation of the unit. For this reason it is necessary that the quantities of fluid be transferred from the inner chamber to the outer chamber at an incre sing rate to compensate for the weight of the material as it is removed from the rotary uni at a constant rate. Computations show that th two opposing tendencies are exactly equal throughout the rotation of the unit.

These embodiments of the invention herein disclosed are illustrative only and may be widely modified and departed from in many ways without departing from thespirit and scope of the invention as pointed out in and limited only by the appended claims.

What is claimed is:

1. In a material handling apparatus, a unit rotatable about anaxis, a material supporting member carried by the unit, means to cause variation in the quantity of a material supported by the member, Weight means, and means controlled by variation in the quantity of the material on the support to cause movement of quantities of the weight means varying distances from the axis to balance the unit.

2. In a material handling apparatus, a balanced rotary unit, means tending to unbalance the unit, and movable Weight means controlled by the said first named means to maintain the unit balanced.

3. In a material handling apparatus, a. rotary unit, a rotary element carried by the unit for supporting material removable during rotation of the unit to cause rotation of the element, movable weight means, and means actuated by the rotation of the element to cause movement of the weight means.

4. In a material handling apparatus, a rotary unit, a rotary element carried by the unit for supporting material removable during rotation of the unit to cause rotation of the element, a fluid Weight means, and means actuated by the rotation of the element to cause movement of the weight means. A

5. In a material handling apparatus, a rotary unit, an element carried by the unit to` support material removable during rotation of the unit, a uid carried by the unit, and means affected by the removal of the material to free the fluid for movement of the fluid by centrifugal force to balance the unit.

6. In a material handling apparatus, a rotary unit, an element carried by the unit to support material removable during rotation of the unit, a iiuid carried by the unit, and means affected by the removal of the material to free the fluid in quantities proportional in Weight to the Weight of the material being removed `from the pad for movement of the iiuid by centrifugal force to balance the unit.

7. In a material handling apparatus, a balanced rotary unit including a substance of predetermined weight, means to remove continuous quantities of the substance resulting in a decrease in the weight thereof during rotation of the unit,

weight to the decrease in weight of the substance to maintain the unit balanced.

8. In a material handling apparatus, a balanced rotary unit including a substance of predetermined weight, means to remove continuous quan-t tities of the substance resulting in a vdecrease in the Weight thereof during rotation of the unit, a fluid of a weight comparable to the Weight of the substance, compartmentsfor the uid, and means controlled by the removal of the substance to transfer the iiuid from one compartment to another in quantities proportional in weight to the decrease in weight of the substance to maintain the unit balanced.

9. In a material handling apparatus, a balanced rotary unit including a substance of predetermined weight, means to remove continuous quantities of the substance resulting in a decrease in the weight thereof during rotation of the unit, a fluid of a Weight comparable to the weight of the substance, chambers for the fluid disposed varied distances from the axis of rotation of the unit, and means to free quantities of the fluid from one of the chambers to be moved by centrifugal vforce into the other chamber to maintain the unit balanced.

10. In a material handling apparatus, a balanced rotary unit including a substance of predetermined weight, means to remove continuous quantities of the substance resulting in a decrease in the weight thereof during rotation of the unit, a fluid of a Weight comparable to the weight of the substance, chambers for the fluid disposed varied distances from the axis of rotation of the unit, means to free quantities of the iiuid from one of the chambers to be moved by centrifugal force into the other chamber to maintain the unit balanced, and means to cause the fluid to return to the rst chamber.

11. In a material handling apparatus, a balanced rotary unit including a substance of predetermined Weight, means to remove continuous quantities of the substance resulting in a decrease in Weight thereof during rotation of the unit, a fluid of a Weight comparable to the weight of the substance, chambers for the fluid disposed varied distancesfrom theaxis of rotation of the unit, and means controlled by the removal of the substance to free the fluid from one chamber to pass into the other by centrifugal force to cause an increase in the effective Weight of the fluid proportional to the decrease in Weight of the substance.

12. In a material handling apparatus, a balanced Arotary unit including a substance, means to remove quantities of the substance causing a decrease in the Weight thereof and tending to unbalance the unit, a fluid, and means to shift the fluid to compensate for the decrease in the weight of the substance to maintain the unit balanced.

13. In a material handling apparatus, a balanced rotary unit, elements carried by the unit at spaced positions for supporting pads of material, means to remove material from the pads at varying rates causing a decrease inthe Weight thereof, and means affected by the removal of the material from each pad to compensate for the decrease in Weight thereof.

14. In a material handling apparatus, a bal.- anced rotary unit having a pivotal frame, means to removably latch the frame against displacement, a rotary element carried by the frame for supporting a pad of material, means to cause rotation of the element by causing removal of the material from the pad during rotation of the unit tending to unbalance the unit, a housing carried by the frame and having an inner and outer chamber, a valve having a passageway intermittently communicating with the chambers when actuated, and means controlled by the rotation of the element to actuate the valve to transfer quantities of the fluid from the inner chamber to the outer chamber to maintain the unit balanced.

15.` In a material handling apparatus, a unit rotated about an axis and including a fixed weight at one side of the axis, a support for a substance of a predetermined Weight disposed at another side of the axis, means to remove quantities of the substance resulting in a decrease in weight thereof during rotation of the unit, and weight means disposed at the side of the axis with the substance to maintain the unit balanced.

16. In a material handling apparatus, a unit rotated about arr axis and including a fixed weight at one side of the axis, a support for a substance of a predetermined Weight disposed at another side of the axis, means to vary the weight of the substance on the support, and weight means disposed at the side of the axis with the substance to maintain the unit balanced.

1'?. In a material handling apparatus, a unit rotated about an axis and including a xed Weight at one side of the axis, a support for a substance of a predetermined Weight disposed at another side of the axis, means to move the support to vary the weight of the substance on the support, and weight means disposed at the side of the axis with the substance and controlled by movement of the support to maintain the unit balanced.

18. In a material handling apparatus, a unit rotated about an axis and including a xed Weight at one side of the axis, a support for a substance of a predetermined Weight disposed at another side of the axis, means to vary the Weight of the substance on the support, Weight means, and means to cause movement of quantities of the weight means predetermined distances from and means to cause movement of quantities of the weight means varying distances from the axis to balance the unit.

20. In a material handling apparatus, a unit rotated about an axis and including a xed weight at one side of the axis, a support for a substance of a predetermined Weight disposed at another side of the axis, means to vary the weight of the substance on the support, Weight means, means to cause movement of quantities of the weight means predetermined distances from the axis to balance the unit, and means to vary the said quantities of the weight means.

21. In a material handling apparatus, a unit rotated about an axis and including a rotatable support formaterial removable to cause rotation of the support at varying speeds, and weight means moved by the support at speeds variable with variations in the speed of rotation of the support to balance the unit.

22. In a material handling apparatus, a. unit 1o rotated about an axis and including a rotatable support i'or material removable at a constant rate of speed to cause rotation of the support at a varying rate, fluid weight means, and means controllen by the support to move the weight means at a varying rate' to compensate-for the constant variation caused by the removal of the material to balance the unit.

HARRY H. MERWIN. ELLWOOD W. REYNOLDS. 

